Substrate for 2B6 and 2D6. Phenotiazines in general are considered safe in several references.

High dose phenothiazine used (tabl 5-500 mg/d) as tranquillizer, antiallergic, and against motion sickness. Metabolized by CYPs 2B6 and 2D6, Inhibitor of 2 D6. Used in porphyria ward (Sweden). South African list: use French list: authorized Kalman, Bonkowski: safe Anderson KE: Effects of antihypertensive drugs on hepatic heme biosynthesis, and evaluation of ferrochelatase inhibitors to simplify testing of drugs for heme pathway induction. Biochem Biophys Acta 543:313, 1978: safe Moore MR, Hift RJ: Drugs in the acute porphyrias. Cell Mol Biol 43:89, 1997: safe.

Uneventful use reported in 6 patients with acute porphyria.